Metamath Proof Explorer


Theorem isstruct

Description: The property of being a structure with components in M ... N . (Contributed by Mario Carneiro, 29-Aug-2015)

Ref Expression
Assertion isstruct FStructMNMNMNFunFdomFMN

Proof

Step Hyp Ref Expression
1 isstruct2 FStructMNMN×FunFdomFMN
2 df-3an MNMNMNMN
3 brinxp2 M×NMNMN
4 df-br M×NMN×
5 2 3 4 3bitr2i MNMNMN×
6 biid FunFFunF
7 df-ov MN=MN
8 7 sseq2i domFMNdomFMN
9 5 6 8 3anbi123i MNMNFunFdomFMNMN×FunFdomFMN
10 1 9 bitr4i FStructMNMNMNFunFdomFMN